Helical Strake Attachment for Tubular Structural Members

ABSTRACT

A helical strake pole system that includes a tubular pole having a longitudinal axis and threaded attachment points. The system further includes a helical strake fin disposed circumferentially around a portion of the tubular pole along the longitudinal axis. The system further includes couplers disposed on the tubular pole. The couplers are configured such that each coupler has a first portion with a slot configured to receive an upper portion of the helical strake fin and a second portion configured to removably coupled to a threaded attachment point of the tubular pole. In addition, each coupler is configured to position a portion of the helical strake fin substantially perpendicular to a surface of the tubular pole.

TECHNICAL FIELD

This disclosure relates generally to an attachment for pole systems, andmore specifically to systems and methods for installing helical strakesonto tubular members.

BACKGROUND

Tubular members are prone to induced vibrations. For example, vibrationscan be caused by current flow in water or by wind flow on land. Windinduced vibration of a tubular structural member can produce vibrationsthat adversely affect the member and its function. Classicalvortex-induced vibration results from vortex shedding. In this type ofvibration, vortices are created that shed off a member in a rhythm or ata constant frequency when wind flows across the member. Vortices canresult in movement of the member in a direction 90 degrees to thedirection of flow. When the vortex shedding frequency becomes close to anatural frequency of vibration of the member, then lock-in can occurwhich may result in large amplitudes and potentially damagingvibrations.

Helical strakes have been successfully utilized on chimneys, smokestacks, pipelines, and flare stacks in refineries to reduce thepotential for vortex-induced vibrations. Typically, helical strakesconsist of a thin plate bent to helically wrap around the tubularmember. Conventional attachment of strakes requires layout and weldingof the strakes to a tubular member in the field. This process involvessignificant field labor, construction time, and expense. Shippingstrakes pre-welded to a tubular member is undesirable due to potentialshipping damage to the thin strakes and handling concerns. Thus, it isdesirable to provide an improved method for attaching helical strakes totubular members.

SUMMARY

In one embodiment, the disclosure includes a helical strake pole systemthat includes a tubular pole having a longitudinal axis and threadedattachment points. The system further includes a helical strake findisposed circumferentially around a portion of the tubular pole alongthe longitudinal axis. The system further includes couplers disposed onthe tubular pole. The couplers are configured such that each coupler hasa first portion with a slot configured to receive an upper portion ofthe helical strake fin and a second portion configured to be removablycoupled to a threaded attachment point on the tubular pole. In addition,each coupler is configured to position a portion of the helical strakefin substantially perpendicular to a surface of the tubular pole.

In another embodiment, the disclosure includes a helical strake poleassembly method. The method includes positioning a helical strake fincircumferentially around a portion of a tubular pole along alongitudinal axis of the tubular pole. The method further includesattaching a plurality of couplers to the tubular pole such that eachcoupler positions a portion of the helical strake fin substantiallyperpendicular to a surface of the tubular pole. Attaching a coupler tothe tubular pole involves positioning a first portion of the coupler tointerface with the helical strake fin and removably coupling a secondportion of the coupler to a threaded attachment point of the tubularpole.

Various embodiments present several technical advantages, such as asystem that allows allow helical strake fins to be attached to tubularmembers without requiring welding. A helical strake fin is attached to atubular member using a coupler. The coupler is configured to beadjustable to accommodate the effects of taper in the tubular member andfor inconsistencies in the bend and pitch of the helical strake fin.

Certain embodiments of the present disclosure may include some, all, ornone of these advantages. These advantages and other features will bemore clearly understood from the following detailed description taken inconjunction with the accompanying drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this disclosure, reference is nowmade to the following brief description, taken in connection with theaccompanying drawings and detailed description, wherein like referencenumerals represent like parts.

FIG. 1 is a perspective view of an embodiment of a helical strake polesystem;

FIG. 2 is a partial cutaway view of an embodiment of a coupler forattaching a helical strake fin to a tubular pole;

FIG. 3A-3C are partial cutaway views of other embodiments of a couplerfor attaching a helical strake fin to a tubular pole;

FIGS. 4A-4C are partial cutaway views of other embodiments of a couplerwith a threaded portion;

FIGS. 5A-5E are perspective views of embodiments of a coupler; and

FIG. 6 is a flowchart of an embodiment of a helical strake pole assemblymethod.

DETAILED DESCRIPTION

Disclosed herein are various embodiments for coupling a helical strakefin to a tubular member. Conventional strake attachment systems requirelayout and welding of the strakes to a tubular member in the field. Thisprocess involves significant field labor, construction time, andexpense. Shipping strakes pre-welded to a tubular member is undesirabledue to potential shipping damage to the thin strakes and handlingconcerns. In contrast, the techniques and system disclosed herein allowhelical strake fins to be attached to tubular members without requiringwelding. A helical strake fin is attached to a tubular member using acoupler. The coupler is configured to be adjustable to accommodate theeffects of taper in the tubular member and for inconsistencies in thebend and pitch of the helical strake fin.

FIG. 1 is a perspective view of an embodiment of a helical strake polesystem 100. The helical strake pole system 100 comprises a tubular pole102, one or more helical strake fins 104, and a plurality of couplers106.

The one or more helical strake fins 104 may be positionedcircumferentially around the outer diameter of the tubular pole 102. Ahelical strake fin 104 may be configured to have any suitable length andheight which extends radially outward from the surface of the tubularpole 102. In addition, a helical strake fin 104 may be configured withany suitable pitch along the length of the tubular pole 102. A helicalstrake fin 104 may be formed of a metal (e.g. steel or aluminum), acomposite (e.g. fiberglass), or any other suitable material as would beappreciated by one of ordinary skill in the art upon viewing thisdisclosure.

Each coupler 106 is configured to attach to the tubular pole 102 and toattach or support a helical strake fin 104. The couplers 106 may beformed of a metal (e.g. steel or aluminum), a composite (e.g.fiberglass), or any other suitable material as would be appreciated byone of ordinary skill in the art upon viewing this disclosure. Examplesof couplers 106 are described in FIGS. 2, 3A-3C, 4A-4C, and 5A-5E.

An example of the tubular pole 102 includes, but is not limited to, anelectric power transmission pole. In other examples, the tubular pole102 may be any other suitable type of tubular structural member forabove ground or underwater applications. The tubular pole 102 have anysuitable length and diameter (e.g. inner diameter and outer diameter).The tubular pole 102 may be formed of a metal (e.g. steel or aluminum),a composite (e.g. fiberglass), or any other suitable material as wouldbe appreciated by one of ordinary skill in the art upon viewing thisdisclosure. The tubular pole 102 comprises a plurality of threadedattachment points 105 disposed circumferentially around the tubular pole102 and along its longitudinal axis 101. The threaded attachment points105 provide an interface for coupling couplers 106 to the tubular pole102. An example of a threaded attachment point 105 includes, but is notlimited to, a threaded bolt hole, a threaded bolt, or a nut welded ontothe tubular pole 102. The tubular pole 102 may comprise any suitablenumber of threaded attachment points 105 which may be distributedanywhere along the surface of the tubular pole 102. Examples of usingthe threaded attachment points 105 to couple the helical strake fin 104and the couplers 106 to the tubular pole 102 are described in FIGS. 2,3A-3C, 4A-4C, and 6.

FIG. 2 is a partial cutaway view of an embodiment of a coupler 106 forattaching a helical strake fin 104 to a tubular pole 102. A portion 202of the coupler 106 is configured to be removably coupled to a threadedattachment point 105 of the tubular pole 102. For example, the portion202 may comprise one or more holes, slots, or openings that allows bolts204 to pass through the coupler 106 to for attaching the coupler 106 tothe tubular pole 102. In this configuration, the coupler 106 is attachedto the tubular pole 102 using threaded attachment points 105 on opposingsides of the helical strake fin 104. In one embodiment, the coupler 106may be attached to the threaded attachment points 105 using bolts orscrews 204. In other embodiment, the coupler 106 may be attached to thethreaded attachment points 105 using nuts when the threaded attachmentpoints 105 are threaded bolts protruding from the tubular pole 102. Inother embodiments, the coupler 106 may be attached to the threadedattachment points 105 using any other suitable technique for removablycoupling the coupler 106 to the tubular pole 102. In one embodiment, theportion 202 of the coupler 106 may comprise slotted openings that allowthe position of the coupler 106 to be adjusted before securing thecoupler 106 using bolts 204. For example, the coupler 106 may be rotatedwith respect to the surface of the tubular pole 102 to compensate forinconsistencies with the helical strake fin 104 before securing thecoupler 106 to the tubular pole 102.

Another portion 206 of the coupler 106 is configured to receive and/orsupport the helical strake fin 104. The helical strake fin 104 ispositioned within a groove, crimp, slot, or recess 203 of the coupler106. The coupler 106 is configured to position the helical strake fin104 to be substantially perpendicular to the surface of the tubular pole102. In other words, the coupler 106 positions the helical strake fin104 such that it extends radially away from the surface of the tubularpole 102. In one embodiment, the coupler 106 may be formed using apliable or semi-rigid material (e.g. aluminum) that allows the coupler106 shape to be manipulated to compensate for inconsistencies in thebend and pitch of the helical strake fin 104.

FIG. 3A-3C are partial cutaway views of other embodiments of a coupler106 for attaching a helical strake fin 104 to a tubular pole 102. InFIGS. 3A-3C, the coupler 106 is configured to attach to the tubular pole102 on one side of a helical strake fin 104.

In FIG. 3A, a portion 302 of the coupler 106 is configured to beremovably coupled to a threaded attachment point 105 of the tubular pole102. For example, the portion 302 may comprise a hole, slot, or openingconfigured similar to the coupler 106 described in FIG. 2. In oneembodiment, the coupler 106 may be attached to the threaded attachmentpoints 105 using bolts or screws 204. In other embodiments, the coupler106 may be attached to the threaded attachment points 105 using anyother suitable technique for removably coupling the coupler 106 to thetubular pole 102. In one embodiment, the portion 302 of the coupler 106may comprise slotted openings that allow the position of the coupler 106to be adjusted before securing the coupler 106 using bolts 204. Forexample, the coupler 106 may be rotated with respect to the surface ofthe tubular pole 102 to compensate for inconsistencies with the helicalstrake fin 104 before securing the coupler 106 to the tubular pole 102.

Another portion 304 of the coupler 106 is configured to receive and/orsupport the helical strake fin 104. The helical strake fin 104 ispositioned within a groove, crimp, slot, or recess 203 of the helicalcoupler 106. The coupler 106 is configured to position the helicalstrake fin 104 to be substantially perpendicular to the surface of thetubular pole 102. In other words, the coupler 106 positions the helicalstrake fin 104 such that it extends radially away from the surface ofthe tubular pole 102. In one embodiment, the coupler 106 may be formedusing a pliable or semi-rigid material (e.g. aluminum) that allows thecoupler 106 shape to be manipulated to compensate for inconsistencies inthe bend and pitch of the helical strake fin 104. In FIG. 3A, theportion 304 of the coupler 106 configured to receive the helical strakefin 104 substantially covers one side of the helical strake fin 104 andonly partially covers the opposing side of the helical strake fin 104.In other embodiments, the portion 304 may be configured to cover orsupport any other suitable amount of the sides of the helical strake fin104.

In FIG. 3B, the coupler 106 is configured similar to the coupler 106described in FIG. 3A. In this embodiment, the portion 304 of the coupler106 configured to receive the helical strake fin 104 substantiallycovers both sides of the helical strake fin 104. In one embodiment, thecoupler 106 comprises one or more openings for allow bolts 204 to passthrough the coupler 106 to secure the helical strake fin 104 within theslot 203 of the coupler 106. For example, the coupler 106 may beconfigured to receive a first bolt 204A for securing the coupler 106 tothe tubular pole 102 and a second bolt 204B (e.g. a set screw) forcoupling the helical strake fin 104 to the coupler 106. Adjusting thesecond bolt 204B applies a force onto the helical strake fin 104 tocouple the helical strake fin 104 to the coupler 106. In thisconfiguration, the coupler 106 provides mechanical interface forcoupling the helical strake fin 104 with the coupler 106. In someembodiments, the coupler 106 may use multiple set screws to apply aforce onto the helical strake fin 104.

FIG. 3C, is a perspective view of the coupler 106 described in FIG. 3B.In this embodiment, the coupler 106 comprises a single opening 306 forreceiving a bolt 204 to attach the coupler 106 to a tubular pole 102. Inother embodiments, the coupler 106 may comprise any other suitablenumber of openings 306 for receiving bolts 204 to attach the coupler 106to a tubular pole 102.

FIGS. 4A-4C are partial cutaway views of other embodiments of a coupler106 with a threaded portion. In FIGS. 4A-4C, the coupler 106 isconfigured to employ a threaded portion that allows the coupler 106 toadapt to variations in the height a helical strake fin 104.

In FIG. 4A, a portion 402 of the coupler 106 is configured to beremovably coupled to a threaded attachment point 105 of the tubular pole102. For example, the portion 402 may comprise a hole, slot, or openingconfigured similar to the coupler 106 described in FIG. 2. In oneembodiment, the coupler 106 may be attached to the threaded attachmentpoints 105 using bolts or screws 204. In other embodiments, the coupler106 may be attached to the threaded attachment points 105 using anyother suitable technique for removably coupling the coupler 106 to thetubular pole 102. In one embodiment, the portion 402 of the coupler 106may comprise slotted openings that allow the position of the coupler 106to be adjusted before securing the coupler 106 using bolts 204. Forexample, the coupler 106 may be rotated with respect to the surface ofthe tubular pole 102 to compensate for inconsistencies with the helicalstrake fin 104 before securing the coupler 106 to the tubular pole 102.

Another portion 404 of the coupler 106 is configured to receive and/orsupport the helical strake fin 104. The helical strake fin 104 ispositioned within a groove, crimp, slot, or recess 203 of the coupler106. The coupler 106 is configured to position the helical strake fin104 to be substantially perpendicular to the surface of the tubular pole102. In other words, the coupler 106 positions the helical strake fin104 such that it extends radially away from the surface of the tubularpole 102. In one embodiment, the coupler 106 may be formed using apliable or semi-rigid material (e.g. aluminum) that allows the coupler106 shape to be manipulated to compensate for inconsistencies in thebend and pitch of the helical strake fin 104. In FIG. 4A, the portion404 of the coupler 106 configured to receive the helical strake fin 104only partially covers the sides of the helical strake fin 104. In otherembodiments, the portion 404 may be configured to cover or support anyother suitable amount of the sides of the helical strake fin 104.

The coupler 106 further comprises a threaded portion 406. In oneembodiment, the threaded portion 406 may be provided by the bolt 204used to attach the coupler 106 to the tubular pole 102. In anotherembodiment, the threaded portion 406 may be provided using a differentbolt or threaded rod. The threaded portion 406 is configured to adjustthe position of the portion 404 of the coupler 106 with respect to thelength of the threaded portion 406. In other words, the threaded portion406 allows the coupler 106 to adapt for short or taller helical strakefins 104. This feature allows the coupler 106 to be adjusted tocompensate for inconsistencies in the height of the helical strake fin104.

In FIG. 4B, the coupler 106 is configured similar to the coupler 106described in FIG. 4A. In this embodiment, the portion 404 of the coupler106 configured to receive the helical strake fin 104 covers of thesurface of the helical strake fin 104 on both sides of the helicalstrake fin 104. In some embodiments, the coupler 106 comprises one ormore openings for allow bolts 204 to pass through the coupler 106 tosecure the helical strake fin 104 within the slot 203 of the coupler 106similar to the configuration described in FIG. 3B. In thisconfiguration, the coupler 106 provides mechanical interface forcoupling the helical strake fin 104 with the coupler 106.

In FIG. 4C, the coupler 106 is configured similar to the coupler 106described in FIG. 4A. In this embodiment, the portion 404 of the coupler106 comprises a first slot 203A configured to receive a first portion(e.g. an upper portion) of the helical strake fin 104 and a second slot203B configured to receive a second portion (e.g. a lower portion) ofthe helical strake fin 104. The first slot 203A and the second slot 203Bmay be configured to cover any suitable amount of the surface of thehelical strake fin 104. In this configuration, the coupler 106 providessupport at both ends of the helical strake fin 104 for coupling andmaintaining the position of the helical strake fin 104 with respect tothe tubular pole 102.

FIGS. 5A-5E are perspective views of embodiments of a coupler 106. Inone embodiment, the couplers 106 illustrated in FIGS. 5A-5E may be usedand configured similar to the couplers 106 described in FIGS. 2, 3A-3C,and 4A-4C.

FIG. 6 is a flowchart of an embodiment of a helical strake pole assemblymethod 600. Method 600 may be implemented by a technician or installerto attach a helical strake fin 104 to a tubular pole 102. In oneembodiment, the technician may attach the helical strake fin 104 to thetubular pole 102 in the field or at a work site. In other embodiments,the technician may attach the helical strake fin 104 to the tubular pole102 at a different location before delivering the helical strake polesystem to a distributor, an end-user, or work site. The assembledhelical strake pole system may employ couplers 106 similar to thecouplers 106 described in FIGS. 2, 3A-3C, 4A-4C, and 5A-5E and/orsimilar variations.

At step 602, a technician positions a helical strake fin 104circumferentially around a portion of a tubular pole 102. The technicianpositions the helical strake fin 104 around the outer diameter of thetubular pole 102. Any suitable length of the helical strake fin 104 maybe disposed onto the tubular pole 102.

At step 604, the technician positions a first portion of the coupler 106to interface with the helical strake fin 104. For example, thetechnician may position a portion of the helical strake fin 104 within aslot 203 of the coupler 106. The slot 203 of coupler 106 may partiallyor substantially cover the sides of the helical strake fin 104.

In one embodiment, the technician may install or adjust a set screw 204in the first portion of the coupler 106 to couple the helical strake fin104 with the coupler 106. In this example, adjusting the set screwapplies a force onto the helical strake fin 104 to couple the helicalstrake fin 104 to the coupler 106.

In one embodiment, the technician may adjust the height of the firstportion of the coupler 106 with respect to a threaded portion of thecoupler 106. In this example, the technician may raise or lower theheight of the first portion of the coupler 106 to interface and securethe helical strake fin 104.

At step 606, the technician couples a second portion of a coupler 106 toa threaded attachment point 105 of the tubular pole 102. For example,the technician may use one or more bolts 204 to removably couple thecoupler 106 to the tubular pole 102, and thereby, couple the helicalstrake fin 104 to the tubular pole 102. The coupler 106 may be fastenedto the tubular pole 102 on one or both sides of the helical strake fin104. The technician may rotate the first portion and/or the secondportion of the coupler 106 about the threaded attachment point 105 priorto securely fastening the coupler 106 to the tubular pole 102. In someembodiments, the technician may apply adhesive or a thread locker to thethreaded attachment points 105 to provide a more secure connectionbetween the threaded attachment points 105 and the bolts 204.

The technician may repeat steps 604 and 606 any suitable number of timesto attach additional couplers 106 to the tubular pole 102 to support thehelical strake fin 104.

While several embodiments have been provided in the present disclosure,it should be understood that the disclosed systems and methods might beembodied in many other specific forms without departing from the spiritor scope of the present disclosure. The present examples are to beconsidered as illustrative and not restrictive, and the intention is notto be limited to the details given herein. For example, the variouselements or components may be combined or integrated in another systemor certain features may be omitted, or not implemented.

In addition, techniques, systems, subsystems, and methods described andillustrated in the various embodiments as discrete or separate may becombined or integrated with other systems, modules, techniques, ormethods without departing from the scope of the present disclosure.Other items shown or discussed as coupled or directly coupled orcommunicating with each other may be indirectly coupled or communicatingthrough some interface, device, or intermediate component whetherelectrically, mechanically, or otherwise. Other examples of changes,substitutions, and alterations are ascertainable by one skilled in theart and could be made without departing from the spirit and scopedisclosed herein.

To aid the Patent Office, and any readers of any patent issued on thisapplication in interpreting the claims appended hereto, applicants notethat they do not intend any of the appended claims to invoke 35 U.S.C. §112(f) as it exists on the date of filing hereof unless the words “meansfor” or “step for” are explicitly used in the particular claim.

1.-20. (canceled)
 21. A helical strake system, comprising: a tubularstructural member having a longitudinal axis and comprising a pluralityof threaded attachment points; a helical strake fin disposedcircumferentially around a portion of the tubular structural memberalong the longitudinal axis; a plurality of couplers disposed on thetubular structural member, wherein: each coupler comprises: a firstportion comprising a slot configured to receive an upper portion of thehelical strake fin; and a second portion configured to be removablycoupled to a threaded attachment point of the tubular structural member;and each coupler configured to position a portion of the helical strakefin substantially perpendicular to a surface of the tubular structuralmember.
 22. The system of claim 21, wherein: the second portion of thecoupler is coupled to: a respective first attachment point on one sideof the helical strake fin; and a respective second attachment point onan opposing side of the helical strake fin.
 23. The system of claim 21,wherein: the slot in the first portion of each coupler is configured to:substantially cover one side of the helical strake fin disposed withinthe coupler; and partially cover an opposing side of the helical strakefin disposed within the coupler.
 24. The system of claim 21, wherein:the slot in the first portion of each coupler is configured to:substantially cover one side of the helical strake fin disposed withinthe coupler; and substantially cover an opposing side of the helicalstrake fin disposed within the coupler.
 25. The system of claim 21,wherein the first portion of each coupler comprises a set screwconfigured to apply a force onto a portion of the helical strake fin.26. The system of claim 21, wherein: the second portion of each couplercomprises a second slot configured to receive a lower portion of thehelical strake fin.
 27. The system of claim 21, wherein: each couplercomprises a threaded portion; and the position of the first portion ofeach coupler is adjustable along the threaded portion.
 28. The system ofclaim 27, wherein the first portion of each coupler is configured torotate about the threaded portion.
 29. The system of claim 27, whereinthe second portion of each coupler is configured rotate about thethreaded portion.
 30. The system of claim 27, wherein the threadedportion of each coupler is a bolt configured to attach the coupler tothe threaded attachment point of the tubular structural member.
 31. Ahelical strake structural member assembly method, comprising:positioning a helical strake fin circumferentially around a portion of atubular structural member along a longitudinal axis of the tubularstructural member, wherein the tubular structural member comprises aplurality of threaded attachment points; attaching a plurality ofcouplers to the tubular structural member, wherein: each coupler isconfigured to position a portion of the helical strake fin substantiallyperpendicular to a surface of the tubular structural member; andattaching a coupler to the tubular structural member comprises:positioning a first portion of the coupler to interface with the helicalstrake fin, wherein the first portion comprises a slot configured toreceive an upper portion of the helical strake fin; and removablycoupling a second portion of the coupler to a threaded attachment pointof the tubular structural member.
 32. The method of claim 31, whereinattaching the coupler comprises attaching the second portion of eachcoupler to: a respective first threaded attachment point on one side ofthe helical strake fin; and a respective second threaded attachmentpoint on an opposing side of the helical strake fin.
 33. The method ofclaim 31, wherein the slot in the first portion of each coupler isconfigured to: substantially cover one side of the helical strake findisposed within a coupler; and partially cover an opposing side of thehelical strake fin disposed within the coupler.
 34. The method of claim31, wherein the slot in the first portion of each coupler is configuredto: substantially cover one side of the helical strake fin disposedwithin the coupler; and substantially cover an opposing side of thehelical strake fin disposed within the coupler.
 35. The method of claim31, wherein attaching the coupler comprises adjusting a set screw in thefirst portion of the coupler, wherein adjusting the set screw applies aforce onto a portion of the helical strake fin.
 36. The method of claim31, wherein the second portion of each coupler comprises a second slotconfigured to receive a lower portion of the helical strake fin.
 37. Themethod of claim 31, wherein: each coupler comprises a thread portion;and attaching the coupler comprises adjusting the position of the firstportion of the coupler with respect to the threaded portion.
 38. Themethod of claim 37, wherein the first portion of each coupler isconfigured to rotate about the threaded portion.
 39. The method of claim37, wherein the second portion of each coupler is configured rotateabout the thread portion.
 40. The method of claim 37, wherein: thethreaded portion of each coupler is a bolt; and attaching each couplercomprises attach each coupler to the threaded attachment point of thetubular structural member using the bolt.